This invention relates to carbacephem and cephem compounds having an antibacterial activity and a substituted thio group at the 3-position, and pharmaceutical compositions containing the same.
Many patent applications have so far been field for cephem or carbacephem compounds, among which ceftizoxime, cefmenoxime, ceftriaxone, etc. are known as those having a heterocyclic thio group at the 3-position. As a cephem compound having a heterocyclic thio group at the 3-position, a compound represented by the formula: ##STR4## (wherein R.sub.A is a heterocyclic group) is disclosed in Japanese Published Unexamined patent application Ser. No. 38392/1980, which corresponds to EP 9008-A, and a compound represented by the formula: ##STR5## (wherein R.sub.B is a heterocyclic group) is disclosed in Japanese Published Unexamined patent application Ser. No. 83492/1977, which corresponds to U.S. Pat. No. 4,256,739. As to a carbacephem compound, a patent application was filed for a compound represented by the formula: ##STR6## (wherein R.sub.C and R.sub.D have the same meanings as R.sub.1 and R.sub.2 defined hereinafter, respectively) by the present applicant (U.S. patent application Ser. No. 702,623 filed on Feb. 19, 1985, U.S. Pat. No. 4,640,919).
Antibiotics having wide antibacterial spectrum and strong antibacterial activity are always in demand.